1. Field of the Invention
The present invention relates to a swinging bucket centrifuge rotor and, more particularly, to a centrifuge rotor providing higher rotor performance, greater rotor strength, and a decreased manufacturing cost.
2. Description of the Prior Art
Swinging bucket-type centrifuge rotors including a plurality of rotor buckets supported on trunnion pins disposed at the ends of outwardly extending support arms are well known in the art. Such rotors have included both integral and separable or removable trunnion pins. Rotors with integral trunnions are relatively expensive to manufacture. Prior rotors with removable trunnion pins have generally necessitated the separation of pairs of pins mounted at the end of each arm to permit assembly of the pins into the arms, such as by press fitting or threading the pins into the arms. Such assemblies have been relatively complicated and expensive.
In my prior U.S. Pat. No. 3,722,791, issued Mar. 27, 1973, for Centrifuge Rotor With Removable Trunnion Pins, there is disclosed and claimed an improved centrifuge rotor including outwardly extending arms which accommodate removable trunnion pins which cooperate with one another under centrifugal forces. Such centrifuge rotor represents a substantial improvement in the state of the art. It is the primary object of the present invention to improve the state of the art still further.
The power required to drive and cool a centrifuge rotor in an atmospheric environment increases exponentially with diameter. It is therefore very important that a given volume of sample be carried in the smallest possible diametral envelope. Previous designs, including the design of my prior patent, have used separate pins for each of the pivot surfaces which require significant circumferential spacing of the pins to prevent interference of the holes in the support arms. This circumferential spacing increases the total rotor diameter. Such designs also require a large number of machining operations.
Still further, previous designs, including the design of my prior patent, use rotor bucket supports having cavities or pockets therein which are cut parallel to the axis thereof. This maximizes the amount of material removed, which greatly reduces the beam strength of the support as it is taken from a point which is the furthest from the neutral axis of the beam. Thus, prior rotor bucket supports have had insufficient strength for a variety of applications.